Process of copper separation.



- PATENTED MAR. 13, 1906.

APPLICATION FILED DBU.19, 1904.

I subject of the of California,

' I videa process for the separation of copper;

with copper in such J of the coppenileaving the use in the ore for treatment 1n the usual manumrnnsrnrns v a ALEXANDER Emm t To al l whom, it may concern- I,

Y Be it known that I, ALEXANDER ELLIOTT, a

7 King of the United Kingdom of Great Britain and Ireland, residing at Littlerock; in the v have discovered and invented a" new and useful Process of Copper Separation," of which the following is a'specification.

he main object of this invention is to pro- Vide for the e traction of copper from its ores at a minimum of expense. v A further object of the invention is to provide a process for the separation of copper from lowgrade ores thecopper values of whichdo' not warrant the application of the usual processes.

"Another'object of the invention is to pro.- vide 'a processwhich can be successfully used in the separation of copper from, ores containing basesfisuch as lime, iron, &c.in such quantityjis to. be unavailable in the usual processes, such. as by leaching by acid solutions. The present invention leachin the ores by a non acid' solution.

Anot er object of the invention is to proom ores containingipreciousmetalsa ong with the economica treatment of the ores. the invention provides cyaniding or similar for initialv se. aration gold and s1 ver valneri Another object of the invention isto pro- 'de a, process which will be continuous, the e proce ss,so that a limited quantity of reagent used in starting the process will serve for an indefinite amount of ore. i

I have discoveredthat by subjectingores v1 reagent used being regenerated in the course of which contain the copper in,combination the action of ferrous-sulfate with oxygento solutionand assing air through the solution the co 'perwi l be dissolved. outas sulfate,.es-. pecial y if the solution is hot, and my pres ent invention is based on this discovery. The solution does not, take place with non-0Xi-;: dized oresof copper,

such as sulfide, and my invention is applied n 0011I160121O11 .W1tl1 ores which are naturall theoxids endear onates, or toores which I have been converted to this condition, as by.

roastin The word oxidized is therefore Specification ofLetters Patent, Application filfid December '19, 1 c an No. 287,423.

county of Los Angeles, State.

provides for uantities as to interfere.

In this connection p in oxidized condition, as

. PATENT .orrron;

LirrnnnooK, CALIFORNIA; Pfiocess 'oF COP ER .SEP

ARA'TIQ'NI Patented March 13, 1906.

vhereiniused as including either the natural or .artifi'cially produced' condition of combina- 'tion with oxygen.

The process is intended for application to said, and'ln a l it to no -ox enous or sulfurous oreg li dliis sulfids, it is requisite to first oxidize the ores, as by roasting.

The process consists,

the action of anon-acid solution of ferrous sulfate in the presence of in'g the copper, and in draining ofi the co per solution and'separating the copper therel om inanysuitablemann'er, as by filtering, decan- .tation,.-or precipitation. In thi tion-ferrous sulfate will be left in'the solution new supply of ore. The ferrous sulfate solu- Qtionis preferably hot. During the leaching operation the ferrous'sulfate is oxidized to ferric sulfate by the'action of the air, -such ferric sulfate being thereby presented in a to act on the copper oxid in the most effecti ge and rapid manner The accompanying drawing illustrates an apparatus suitable for the carrying out of the process. 1 Y a 1 designates .the firstleaching tank or vat; 2, the second-leaching tank a lower level than the vat 1. v 3; designates the. settling-tank.

4 designates theprecipitating tank or vat, and 5 is the sump-tank.

, Each of the leaching-vats has a filter 6 and a heating-coil 7 belowthefilter, which may be supplied with steam through the steamsupply connectionsl. Said coils are prefe'rab y perforated to'al lowthe-steam to escape into the tanks to agitate-the solutlonin the opening below .the filter air is preferably heated, as by means of a [heater 10.

11 designates means for-supplying air unli orcarrying out the process continuously a conduit or connection 12 is provided, leadleaching-tank, sa connection including a j pump 13 for pumping back the fluid.

s precipitaand willbe used in repeating the process on aor vat, located at bath and the materials therein, a

9 designates air-supply pipes or conduits into the respective leaching-tanks to supply air thereto. Such der pressure-for example, an air-compressor.

essentially, in submitt-lngoxidized or-oxygenous sulfur ores to 'air, thereby dissolvnascent state, wherein it will be in condition ing from the sum(p-'tank 'back tofthe first The process is carried out as follows: The ore is assumed to be non-sulfuroussuch as oxid, carbonate, or silicate oresor to have been rendered non-sulfurous by oxidation, as by roasting sulfid ore. The ore having been crushed to a suitable condition for the action of the leaching agent, a higher-level vat or vats and a lower-level vat or vats are charged therewith. A solution of ferrous sulfate of sufficient strength and quantity to take up when oxidized to ferric sulfate all the cop er in the ore is placed in the first vat. he quantity of sulfate required will depend u on the amount of copper in the ore and will be determined in accordance with the equation hereinafter given. To produce a rapid solution there should be a slight excess of ferrous sulfate. The material in the first tank is heated by the steam-coil, and air is admitted thereto, preferably in a heated condition, with the result that the ferrous sulfate is oxidized to ferric sulfate. The ferric sulfate under the action of heat dissolves the copper in the ore and deposits iron in the form of ferric oxid. The steam escaping from the coil into the tank agitates the materials therein and facilitates and hastens the action. It is found that the leaching action of the ferric sulfate is greater at a higher temperature, and the leaching operation is preferably carried out at a temperature of about the boilingpoint of water. Having found by test that all the copper is extracted from the ore in the first vat, the solution is then run into the sec ond vat or leachin -tank, where the same operation is repeated to allow it to exchange its remaining iron, &e., for copper, so that the copper solution when run into the precipitating-tank will contain no ferric salt, The presence of ferric salt would tend to make an impure copper by the deposit of ferric oxid. An air-supply pipe 9 may lead to the second leachii'ig-tank to supply air thereto when it is desiredfto complete the solution of the copper therein. After leaching the material may be washed repeatedly until all the copper sulfate is removed and recovered. The copper solution is then run into the settling tank or tanks 3, where it remains until all sediment has settled to the bottom. The copper-sulfate solution is then run off or decanteil into the precipitating-tank 4, and by means of scrap-iron, with the aid of heat, or by electrolysis, or in other suitable manner the copper is precipitated and extracted therefrom. The wastesolution after the copper is taken out is run into the sump-tank 5. Said waste solution contains practically all the ferrous sulfate which was put into the ieacliingwat and is pumped throu h the pump l2 onto a new charge of ore int c first lcacliiiig-vnt, where it undergoes the same series of operations above described. By a small addil ion of sulfate each time to-tho s0- linioii its full strength can beniaintained.

siiiese The reactions which occur in the above op erations are as follows:

First. Oxidation of the ferrous sulfate to ferric sulfate:

GFBSOl-f' 2F62 S04 s F0203. Second. The leaching operation I Third. Precipitation:

CuSOi+Fe=Ou+FeSOi.

While the method of oxidizing the ferrous salt described above is by means of air, I do not confinemyself to it, but claim the right to use other suitable means to bring about the same result. The ferrous salt ma be oxidized before adding it to the ore, i desired.

In applying the process to the sulfid ores it is necessary, as above stated, to first roast the ores to remove substantially all the sulfur therefrom.

The process is applicable with advantage to the separation 0 copper from ores containin that metal in conjunction with gold and si ver, the result of the process in that case being that the ore is left with substantially the full gold and silver content, but free from copper, so that it is in suitable condition for the use of cyanid or other treatment for the recovery of the precious metals without the loss which would result from the application of such treatment to the raw oreon account of the presence of co per. The present process renders it possib e to treat the ores for the recovery of gold and silver therefrom in cases where the presence of coper therein would otherwise prevent satisactory and economical operation. The process is also of especial advantage in connection with ores containing bases, such as lime or iron, in such quantities as to interfere with the application of the usual acid leaching agent. The leaching agent in this case being non-acid is not affected by the prcsence of such bases, and the latter are without deleterious effect on the operation.

What I claim is 1. The process of leaching oxidized copper ores which consists in submitting the ore to the action of a non-acid solution of ferrous sulfate and passing air through the solution during the operation of leaching.

2. 'The process of leaching oxidized copper ores which consists in submitting the ore to the action of a hot non-acid solution of ferrous sulfate and passing air through the solution during the operation of leaching.

3. The process of separatiiig cop ier from oxidized ores which consists in leac ing the ore with a hot non-acid solution of ferrous sulfate, passing air through the solution durf from the sollitibrl b 'lmeans gmeens of iron arid' utilizing the resu1tir1g sor II'OIIyt ereb'jireg feuerating the ferrous sulfate lution of ferrous sulfate fora repetition of the I for a re etitio'nb r Y w the proess. process. r

l e propssofseparating cogliier from' In testimony whereof I have hereuntb set 5 ores containing besic'g'angue, whic inleac hing the ore with a hot n n-aeid solu- 10th dizyzof Deeember, 1904, tionofferrous sulfate,"passing air through ALEXANDER ELLIOTT. thejsolution during the operation of leaching, T In presence of-l v sepgratingthe solution from the residue, pre- 1 ARTHUR .P. KNIGHT,

-10 clprtatingjthe copper from the' solution'b'y l; FREDERICK SJLYO consists my hand," at Los Angeles Oalifornia, this 1 5 

